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enCopyright 20152015-03-27T16:07:10+00:00Who Were the Ancient Engineers of Egypt?Thu, 01 Mar 2007 13:19:00 EDTinfo@csicop.org ()http://www.csicop.org/sb/show/who_were_the_ancient_engineers_of_egypt
http://www.csicop.org/sb/show/who_were_the_ancient_engineers_of_egyptAncient astronauts: The term has a ring to it, conjuring up visions of lost civilizations, extraterrestrial visitors to primitive earthly civilizations, and high intellectual adventure. No one who has read science fiction in his youth can forget those marvelous short stories that ended with the revelation that the planet on which the spacefaring voyagers had landed (or been shipwrecked) was actually the earth. So when Eric von Däniken published Chariots of the Gods?, there was a ready-made audience for him—an audience (including this author) that somewhere deep down wanted to believe that the human race got a helping hand from some old, benevolent culture that even now might be waiting to help us again if we should flounder. It’s a comforting thought. Unfortunately, there’s a big gap between wishing that a particular idea were true and actually finding evidence in support of it.

Unless you are prepared to reveal what happened on every spot on the earth since the beginning of civilization, there is no way to prove that extraterrestrials have not landed on the earth. This means that the question of whether such an event has occurred really boils down to asking whether or not there is compelling evidence of such visitation now, either in literature or in the remains of old civilizations. The ancient-astronaut arguments usually rely on both kinds of evidence, but I’d like to concentrate on just one—the evidence for ancient astronauts as revealed in the building technology of ancient civilizations.

The study of the history of technology has been a growing field for a long time, and we know a surprising amount about the way that things were done in ancient times. We can use this knowledge to set up a couple of guidelines that will help us evaluate the claims used by Von Däniken and others about extraterrestrial help to explain this or that technological advance.

One thing we know about technological change is that it is continuous, although it may proceed faster at one time than at another. Each step in the building of a technology makes use of previous steps. For example, our ability to put up skyscrapers depends on the development of structural steel, the harnessing of energy to run cranes and other large machines, the use of electricity, and countless other things.

To make this point clear, imagine what would happen if somehow all of the evidence of European civilization in North America were removed, so that the continent was returned to its pristine state, except for one thing. Suppose that whoever or whatever accomplished this task forgot to remove the Sears Tower in Chicago. Suppose then that some future anthropologist were to visit this building. He would see a structure which would have required a vast industrial backup system, but there would be no evidence of anything of the kind. In such a situation, he would clearly be justified in concluding that there was more to the situation than met the eye and that something like an ancient- astronaut hypothesis would be needed to explain what he saw.

Of course, this example is pretty extreme—the Sears Tower would be just as out of place in the Gay Nineties as it would be in 1600. There would be no tradition showing the Sears Tower as the culmination of a long period of development in which people learned to construct tall buildings, and in its own way, this sort of situation would be just as startling as if the building really existed all by itself.

So the first question we have to ask about any claim that a particular technological advance required the existence of outside help is this: Is there a continuous technological tradition of which this particular event or structure is a part? If the answer to this question is yes, then the need to assume the existence of outside help becomes less stringent.

There is another question we can ask that is similar to the first one but that depends a little more on our knowledge of ancient technologies. Going back to our example of the Sears Tower, one of the reasons it would have been out of place in the 1890s is that engineers at that time lacked the technological ability to put the building together. Thus, even if the question of the technological tradition were unclear, our imaginary anthropologist would be justified in looking for outside assistance if he knew that the people living around the building simply lacked the ability to do the job. So the second question we have to asks is: Did the local population possess the means to carry out the feat, regardless of whether there was a tradition leading up to it or not?

I would suggest that if we look at some ancient engineering achievement and find that the answer to both of these questions is yes—that is, that the building is the culmination of a long tradition and was within the technological capabilities of the builders—we would be justified in saying that no ancient astronauts were needed to construct the building. I would further suggest that common sense (or the principle of sufficient reason, if you have a more formal turn of mind) then demands that we reject that particular building as evidence for ancient astronauts.

The most striking example of an ancient building that has been put forward as evidence for the existence of ancient astronauts is the Great Pyramid of Giza, near Cairo, Egypt. The reasons for this are not hard to grasp, since the statistics on the pyramid are truly mind boggling (see the box above). It remains the largest stone structure ever erected, consisting of more than 2 million blocks of stone, weighing more than a ton each. If the stone in the pyramid were cut into blocks one foot on a side and these blocks were laid end to end, they would make a line reaching from San Francisco to Moscow and back again!

How in the world could something like this have been built by people who didn’t even use the wheel? Surely, the Egyptians could not have carried out a project of this magnitude without outside help, and, since there were no other civilizations on earth more advanced than the Egyptians at that time, this outside help must have come from extraterrestrials. This, in essence, is the argument of Von Däniken and others.

There is certainly a strong temptation to agree with this assessment when we look at the pyramids, but suppose we stop for a few minutes and ask the two questions we talked about earlier.

The pyramids are apparently burial places for pharaohs, so the way to approach the question about whether or not the Great Pyramid is a break with previous practice is to look at Egyptian burial buildings that were constructed before and after it was built. When I started looking into this question, I discovered some surprising facts. Although there are only three pyramids at Giza, there are literally hundreds of pyramid-shaped tombs scattered up and down the Nile Valley. The group at Giza contains the largest such structure, but that one is neither the first nor the last that was erected.

The first tombs were low brick structures (presumably modeled after houses) built over tomb excavations. These buildings were rectangular in shape and go by the name mastaba. Sometime about 2700 b.c., the shift from building with brick to building with stone was made. This improvement in building techniques, small as it may seem to us, allowed Egyptian engineers to do two things: they could now put up bigger buildings (because of the greater strength of stone) and they could put up buildings which would last longer. As far as burial customs were concerned, the simple rectangular mastaba was elaborated into a structure called a step pyramid, in which successively smaller rectangles are laid on top of each other. The most famous of these is the tomb of Zoser (the man who is supposed to have developed the technique of stone building) at Saqquara, which is a few miles from the site at Giza.

Fortunately for archeologists, the transition from the step pyramid to the more usual pyramid form can be seen in the pyramid at Meidun, where the interior core of a step pyramid was enclosed in a smooth outer coating. Weather and human assaults on the pyramid have removed enough of the outer covering so that the interior structure can be seen. We thus have convincing visual proof that the true pyramid developed when the regular outer walls of the step pyramid were smoothed out. In fact, by the time Cheops began the work on the Great Pyramid at Giza, there were no fewer than three true pyramids already in existence to serve as models. So there is a clear line of evolution from the mastaba to the true pyramid in Egyptian architecture, and the Great Pyramid itself does not mark any radical new ideas.

This fact goes a long way toward refuting another ancient-astronaut argument about the Great Pyramid—that it served some purpose other than that of a burial place for the pharaoh. If a particular structure is clearly part of a long series of buildings, and all of the other buildings are tombs, then there is little reason to suspect that the building in question isn’t a tomb as well. The only thing that differentiates the Great Pyramid from the pyramids that came before and after it is its size.

But size is precisely what enters the picture when we ask the second question: Could the Egyptians have built such a colossal structure without assistance? Because so many claims are made about the building of the pyramids and about the accuracy of the construction involved, it would be a good idea to review some of the salient features of the structure. Its base is approximately square, the sides each being about 756 feet long. The difference between the longest and the shortest side is about eight inches (see the box below). Similarly, the angles of the base differ from a right angle by as little as three degrees of arc.

This means that the base of the pyramid was surveyed to an accuracy of one part in 1000—a truly magnificent feat of engineering for Egyptians equipped with primitive instruments. But if we want to bring in ancient astronauts, there is a serious problem, because modern commercial surveying (the type that might be done in laying out a new housing subdivision) is routinely done to one part in 10,000, ten times better than that of the pyramids, and accuracies considerably higher than this are achieved in places like downtown Manhattan, where every fraction of an inch matters. Thus, the accuracy with which the pyramid is laid out turns out to be an argument against ancient astronauts, since they would surely have been able to do the job at least as well as a modern surveying team.

A similar argument can be made about the claim that the pyramid could not have been built by the Egyptians because if you divide the height by half of the perimeter of the base, you get pi (3.14 . . .). If you check this claim against the actual numbers, you again find that this is true to an accuracy of one part in 1000. So while the Egyptians obviously picked the pyramids’ proportions so that the height was the radius of a circle whose circumference was equal to the circumference of the base of the pyramid, the accuracy was much poorer than we could achieve today. Can you really believe that the members of an advanced race would flunk freshman surveying?

The quality of the stone work can be used to come to the same conclusion. The furnished surfaces of the stone, where needed, were level to within about one fiftieth of an inch. For reference, this is about half the thickness of a dime. A skilled mason using the type of stone-cutting tools found in old Egyptian quarries could, with care, achieve this sort of accuracy. But a spaceman using a laser cutting tool (as has been imagined by some pyramid buffs) would do a couple of orders of magnitude better.

So the workmanship of the pyramid is of a quality that would be just within the reach of what we know the Egyptians of the period could do but is very poor for anyone who had access to modern technology. And if this is true, the only refuge left for the ancient-astronaut notion lies in the claim that the Egyptians simply couldn’t have moved all that stone and put it into place in the pyramid.

This argument has a certain surface credibility. After all, we know that the Egyptians did not use wheeled vehicles at the time of the construction of the Great Pyramid, and there are simply no surviving records which discuss how any of the pyramid construction was actually done. Egyptologists believe, however, that these stones were moved from the quarries in southern Egypt in boats. It turns out that during the annual flood, the Nile used to come to within about a quarter mile of the pyramid site, so that the stones had to be moved only a relatively short distance before being pulled up a sand ramp and set in place.

Some Facts about the Great Pyramid

Approximate amount of stone

57,000,000 tons

Approximate number of blocks

23,000,000

Average block weight

2.5 tons (5,000 pounds)

Weight of largest block

15 tons

Approximate dimensions of base

756 feet on a side

Area of base

13.1 acres

Original height

481.4 feet (31 feet now missing)

The conventional thinking on how the stones were transported is that they were mounted on runners (something like a sled) and then pulled with ropes while water was poured along the path to ease friction. While this may sound difficult, we do have carvings dating from 1,000 years after the building of the pyramids which show a sixty-ton statue being moved in just this way by a team of 172 men. And this was after the Egyptians had the wheel.

Unfortunately, we don’t have much in the way of surviving records to tell us how the pyramids were actually built. The Greek historian Herodotus passes along what he heard from Egyptian priests in his day, and there are some surviving bits of a manuscript by a priest named Manetho, but both of these were written well after the actual building. Estimates of the number of men employed as laborers on the pyramid vary from 400,000 per year to 100,000, working during the three-month inundation season, when they were not needed on farms. Herodotus says that the tradition during his time was that it had taken twenty years to erect the structure. If we take the most conservative estimate of the work force, the question then comes down to this: could 100,000 men have moved 115,000 blocks per years for a twenty-year period? This is the minimum that would have to be done to get all 23,000,000 blocks into place in the allotted time.

Well, the average block weighed two and one half tons, or 5000 pounds—about the weight of a big station wagon or pickup truck. If the work force were split into crews of eight men each, there would be 12,500 crews, and each would have to haul about ten rocks during the three-month period. This amounts to hauling one rock every nine days. So the size of the transportation problem which looks so formidable when we consider the bulk of the pyramid itself looks much more manageable when we bring it down to a more human level. Could eight men haul a station wagon mounted on a wooden sledge two city blocks (a quarter mile) in nine days? There’s no question that they could. So, then the most difficult job in the construction of the pyramids—the moving of the stone blocks—appears to be well within the capabilities of the Egyptians. In fact, when we look at things this way, the truly outstanding feature of the entire project is the organizational skill shown by the builders in coordinating the work of the labor force.

When all is said and done, then, the pyramids, as impressive as they are, give no evidence at all for the presence of advanced technology at work in ancient Egypt. The buildings are manifestly part of a long line of development that stretches back into early history and continues for a thousand years after the Great Pyramid was finished. The building tradition shows no discontinuous breaks of the kind we would have if ancient astronauts had suddenly appeared on the scene. In the same vein, both the construction details and the bulk-transportation system are well within the limits of what we could expect from the technology that we know the Egyptians possessed.

Some Claims about the Great Pyramid

The Great Pyramid is built on bedrock and is therefore invulnerable to earthquakes.

It is indeed built on bedrock, although this doesn’t make it earthquake-proof. Bedrock moves during earthquakes too. And besides, would you really expect a building this size to have a sand foundation?

The Great Pyramid is shaped to deflect meteors.

A really big meteor, like the one that fell in Siberia in the early 1900’s, would destroy the structure completely. From an engineering viewpoint, a hemisphere or geodesic dome would be a much more efficient shape for this purpose.

The Great Pyramid is designed so that the air shafts will be above the water line if the polar ice caps melt.

I would feel more at ease with this argument if most of the chambers and the entrance to the structure were not below the “high water line.” But if you want to take this seriously, then any structure whose top is 200 feet above sea level will serve the purpose. A partial list includes (a) the Empire State Building, (b) the entire city of Denver, and (c) my neighbor’s chicken coop.

It would be impossible to duplicate the Great Pyramid today.

Consider the following facts:

steel girders weighing much more than the pyramid blocks are routinely fitted into place in suspension bridges and atop skyscrapers—a much more difficult task than piling up rocks on a flat plain;

during the flooding following the building of the Aswan Dam, a small group of western construction engineers, using modern earthmoving equipment, disassembled, moved, and reassembled several large temples whose component parts were as large as those of the pyramid.

The reason that no other stone structure as large as the Great Pyramid has been built is really quite simple. The civilization that, after the Egyptians, first started building on a massive scale was that of the Romans, and they had developed concrete. There was simply no call to build with stone any more.